| Message ID | 20220422183610.3127561-1-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++: crash with requires-expr and -Wsequence-point [PR105304] | expand |
On 4/22/22 14:36, Patrick Palka wrote: > Here we're crashing from verify_sequence_points for this requires-expr > condition because it contains a templated CAST_EXPR with empty operand, > and verify_tree doesn't ignore this empty operand only because the > manual tail recursion that it perform for unary expression trees skips > the NULL test. > > Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for > 10/11/trunk? OK. > PR c++/105304 > > gcc/c-family/ChangeLog: > > * c-common.cc (verify_tree) [restart]: Move up to before the > NULL test. > > gcc/testsuite/ChangeLog: > > * g++.dg/cpp2a/concepts-requires30.C: New test. > --- > gcc/c-family/c-common.cc | 2 +- > gcc/testsuite/g++.dg/cpp2a/concepts-requires30.C | 10 ++++++++++ > 2 files changed, 11 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/g++.dg/cpp2a/concepts-requires30.C > > diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc > index 70f55f3a346..bb0544eeaea 100644 > --- a/gcc/c-family/c-common.cc > +++ b/gcc/c-family/c-common.cc > @@ -2009,12 +2009,12 @@ verify_tree (tree x, struct tlist **pbefore_sp, struct tlist **pno_sp, > enum tree_code code; > enum tree_code_class cl; > > + restart: > /* X may be NULL if it is the operand of an empty statement expression > ({ }). */ > if (x == NULL) > return; > > - restart: > code = TREE_CODE (x); > cl = TREE_CODE_CLASS (code); > > diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-requires30.C b/gcc/testsuite/g++.dg/cpp2a/concepts-requires30.C > new file mode 100644 > index 00000000000..f500af3f616 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-requires30.C > @@ -0,0 +1,10 @@ > +// PR c++/105304 > +// { dg-do compile { target c++20 } } > +// { dg-additional-options "-Wall -Wsequence-point" } > + > +struct A { }; > + > +int main() { > + if (requires { A(); }) > + ; > +}
diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc index 70f55f3a346..bb0544eeaea 100644 --- a/gcc/c-family/c-common.cc +++ b/gcc/c-family/c-common.cc @@ -2009,12 +2009,12 @@ verify_tree (tree x, struct tlist **pbefore_sp, struct tlist **pno_sp, enum tree_code code; enum tree_code_class cl; + restart: /* X may be NULL if it is the operand of an empty statement expression ({ }). */ if (x == NULL) return; - restart: code = TREE_CODE (x); cl = TREE_CODE_CLASS (code); diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-requires30.C b/gcc/testsuite/g++.dg/cpp2a/concepts-requires30.C new file mode 100644 index 00000000000..f500af3f616 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-requires30.C @@ -0,0 +1,10 @@ +// PR c++/105304 +// { dg-do compile { target c++20 } } +// { dg-additional-options "-Wall -Wsequence-point" } + +struct A { }; + +int main() { + if (requires { A(); }) + ; +}